docs: def readWarp(self):
          """ Read the warp element
  
          ::
              <warp>
                  <axis name="weight">
                      <map input="0" output="0" />
                      <map input="500" output="200" />
                      <map input="1000" output="1000" />
                  </axis>
              </warp>
  
          """
          warpDict = {}
          for warpAxisElement in self.root.findall(".warp/axis"):
              axisName = warpAxisElement.attrib.get("name")
              warpDict[axisName] = []
              for warpPoint in warpAxisElement.findall(".map"):
                  inputValue = float(warpPoint.attrib.get("input"))
                  outputValue = float(warpPoint.attrib.get("output"))
                  warpDict[axisName].append((inputValue, outputValue))
          self.warpDict = warpDict